#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef double db;

#define in read()
#define pii pair<int,int>
#define fi first
#define se second
#define FILE(x) freopen(x".in","r",stdin);\
	freopen(x".out","w",stdout);
#define pb push_back

int read(){
	int x = 0,sgn = 1;char ch = getchar();
	for(;!isdigit(ch);ch = getchar()) if(ch == '-') sgn = -1;
	for(;isdigit(ch);ch = getchar()) x = (x<<1)+(x<<3)+(ch^48);
	return x*sgn;
}

const int N = 8e5+10;
const int T = 2e5;

int h[N],cnt = 1,ans[N],now[N],n,deg[N];
bool vis[N],v[N<<1];
struct edge{int v,w,nxt;}e[N<<1];
void link(int x,int y,int w){e[++cnt] = (edge){y,w,h[x]};h[x] = cnt;}

void dfs(int x){
	vis[x] = 1;
	for(int i = now[x];i;i = e[now[x]].nxt){
		int y = e[i].v; now[x] = i; if(v[i]) continue;
		ans[e[i].w] = x < y; v[i] = v[i^1] = 1;dfs(y);
	}
}

int main (){
#ifndef ONLINE_JUDGE
	freopen("1.in","r",stdin);
#endif
	n = in;
	for(int i = 1,x,y;i <= n;i++) x = in,y = in,link(x,y+T,i),link(y+T,x,i),deg[x]++,deg[y+T]++;
	int lst = 0;
	for(int i = 1;i <= 2*T;i++){
		if(deg[i] % 2 == 0) continue;
		if(lst) link(lst,i,0),link(i,lst,0),lst = 0;
		else lst = i;
	}for(int i = 0;i <= 2 * T;i++) now[i] = h[i];
	for(int i = 0;i <= 2 * T;i++) if(!vis[i]) dfs(i);
	for(int i = 1;i <= n;i++) printf("%c",ans[i] ? 'b' : 'r');
	return 0;
}
